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	<head>
		<title>three.js webgl - raw shader</title>
		<meta charset="utf-8">
		<meta name="viewport" content="width=device-width, user-scalable=no, minimum-scale=1.0, maximum-scale=1.0">
		<link type="text/css" rel="stylesheet" href="main.css">
	</head>
	<body>

		<div id="container"></div>
		<div id="info"><a href="https://threejs.org" target="_blank" rel="noopener">three.js</a> - raw shader demo</div>

		<script id="vertexShader" type="x-shader/x-vertex">

			precision mediump float;
			precision mediump int;

			uniform mat4 modelViewMatrix; // optional
			uniform mat4 projectionMatrix; // optional

			attribute vec3 position;
			attribute vec4 color;

			varying vec3 vPosition;
			varying vec4 vColor;

			void main()	{

				vPosition = position;
				vColor = color;

				gl_Position = projectionMatrix * modelViewMatrix * vec4( position, 1.0 );

			}

		</script>

		<script id="fragmentShader" type="x-shader/x-fragment">

			precision mediump float;
			precision mediump int;

			uniform float time;

			varying vec3 vPosition;
			varying vec4 vColor;

			void main()	{

				vec4 color = vec4( vColor );
				color.r += sin( vPosition.x * 10.0 + time ) * 0.5;

				gl_FragColor = color;

			}

		</script>

		<script type="module">

			import * as THREE from '../build/three.module.js';

			import Stats from './jsm/libs/stats.module.js';

			let container, stats;

			let camera, scene, renderer;

			init();
			animate();

			function init() {

				container = document.getElementById( 'container' );

				camera = new THREE.PerspectiveCamera( 50, window.innerWidth / window.innerHeight, 1, 10 );
				camera.position.z = 2;

				scene = new THREE.Scene();
				scene.background = new THREE.Color( 0x101010 );

				// geometry
				// nr of triangles with 3 vertices per triangle
				const vertexCount = 200 * 3;

				const geometry = new THREE.BufferGeometry();

				const positions = [];
				const colors = [];

				for ( let i = 0; i < vertexCount; i ++ ) {

					// adding x,y,z
					positions.push( Math.random() - 0.5 );
					positions.push( Math.random() - 0.5 );
					positions.push( Math.random() - 0.5 );

					// adding r,g,b,a
					colors.push( Math.random() * 255 );
					colors.push( Math.random() * 255 );
					colors.push( Math.random() * 255 );
					colors.push( Math.random() * 255 );

				}

				const positionAttribute = new THREE.Float32BufferAttribute( positions, 3 );
				const colorAttribute = new THREE.Uint8BufferAttribute( colors, 4 );

				colorAttribute.normalized = true; // this will map the buffer values to 0.0f - +1.0f in the shader

				geometry.setAttribute( 'position', positionAttribute );
				geometry.setAttribute( 'color', colorAttribute );

				// material

				const material = new THREE.RawShaderMaterial( {

					uniforms: {
						time: { value: 1.0 }
					},
					vertexShader: document.getElementById( 'vertexShader' ).textContent,
					fragmentShader: document.getElementById( 'fragmentShader' ).textContent,
					side: THREE.DoubleSide,
					transparent: true

				} );

				const mesh = new THREE.Mesh( geometry, material );
				scene.add( mesh );

				renderer = new THREE.WebGLRenderer();
				renderer.setPixelRatio( window.devicePixelRatio );
				renderer.setSize( window.innerWidth, window.innerHeight );
				container.appendChild( renderer.domElement );

				stats = new Stats();
				container.appendChild( stats.dom );

				window.addEventListener( 'resize', onWindowResize );

			}

			function onWindowResize() {

				camera.aspect = window.innerWidth / window.innerHeight;
				camera.updateProjectionMatrix();

				renderer.setSize( window.innerWidth, window.innerHeight );

			}

			//

			function animate() {

				requestAnimationFrame( animate );

				render();
				stats.update();

			}

			function render() {

				const time = performance.now();

				const object = scene.children[ 0 ];

				object.rotation.y = time * 0.0005;
				object.material.uniforms.time.value = time * 0.005;

				renderer.render( scene, camera );

			}

		</script>

	</body>
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